Commodore C64 Manual: Service Manual Model C64 Computer (1985-03)(Commodore)[PN-314001-02]

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SERVICE MANUAL
MODEL C64 COMPUTER
MARCH 1985 PN 314001 02

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SERVICE MANUAL
MODEL C64 COMPUTER

MARCH 1985 PN -31 4001-02

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Commodore Business Machines, Inc.

1 200 Wilson Drive, West Chester, Pennsylvania 1 9380 U.S.A.

Commodore makes no expressed or implied war-
ranties with regard to the information contained
herein. The information is made available solely on
an as is basis, and the entire risk as to quality and
accuracy is with the user. Commodore shall not be
liable for any consequential or incidental damages
in connection with the use of the information con-
tained herein. The listing of any available replace-
ment part herein does not constitute in any case
a recommendation, warranty or guaranty as to
quality or suitability of such replacement part.
Reproduction or use without expressed permission,
of editorial or pictorial content, in any matter is
prohibited.

/) This manual contains copyrighted and proprietary information. No part

of this publication may be reproduced, stored in a retrieval system, or
transmitted in any form or by any means, electronic, mechanical,
photocopying, recording or otherwise, without the prior written permis-
sion of Commodore Electronics Limited.

Copyright © 1985 by Commodore Electronics Limited.
All rights reserved.

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CONTENTS

Title Page

SPECIFICATIONS 1

PRODUCT PARTS LIST 2

BLOCK DIAGRAM 3

CIRCUIT THEORY

POWER SUPPLY 4

RESET LOGIC 5

CLOCK CIRCUITS 6

I/O, ROM, EXPANSION PORT 7

RAM CONTROL LOGIC 8

5 PIN VIDEO AND AUDIO OUTPUTS 9

8 PIN VIDEO AND AUDIO OUTPUTS 10

CASSETTE INTERFACE 1 1

KEYBOARD, JOYSTICK & PADDLE INTERFACES 12

SERIAL INTERFACE, USER PORT 13

TROUBLESHOOTING GUIDE 14

BOARD IDENTIFICATION 17

PCB ASSEMBLY #326298-01

BOARD LAYOUT 18

PARTS LISTS 19,20

PIN ASSIGNMENTS 21

SCHEMATIC #326106 21,22

PCB ASSEMBLY #250407-04

BOARD LAYOUT 23

PARTS LIST 24,25

MODULATOR SCHEMATIC #251025 26

SCHEMATIC #251 138 26,27

PIN ASSIGNMENTS 27

PCB ASSEMBLY #250425-01

BOARD LAYOUT 28

PARTS LIST 29,30

/""> MODULATOR SCHEMATIC #251696 31

SCHEMATIC #251469 31,32

PIN ASSIGNMENTS 32

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C64

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GENERAL DESCRIPTION

MEMORY
ROM

MICROPROCESSOR

DISPLAY

COLORS

CHARACTERS

DISPLAY MODES

RESOLUTION

SPRITES

SOUND

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KEYBOARD
KEYS

INPUTS/OUTPUTS

FEATURES

PERIPHERALS

POWER REQUIREMENTS

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COMPUTER

• The "All Purpose" Commodore 64 is the complete computer for
education, home or small business applications. Supported by
quality peripherals and a full range of software, the Commodore 64
is perfect for the family. No other computer can offer such variety
of uses and applications at such an affordable price.

• 64K RAM

• 20K ROM Standard (includes operating system and BASIC
interpreter)

• 651 OA Microprocessor— 1.02 MHz clock • Compatible with
the 6502

• 40 Columns X 25 lines of text

• 1 6 Background, border and character colors

• Upper & lower case letters, numerals and symbols • Reverse
characters • All PET graphic characters

• Text characters • High resolution graphics

• 320 X 200 Pixels

• 8 independent sprites • Each consists of 24 X 21 pixels and
up to 4 colors • Each independently expandable horizontally
and vertically • Collision detection for sprite to sprite and data
to sprite collisions

• 6581 Sound Interface Device includes 3 independent tone
generators— each with 9 octaves • Each voice includes
programmable ADSR generator (Attack, Decay, Sustain, Release)
and control of sawtooth, triangle, square, variable pulse and noise
waveforms • Full filtering capabilities with low, high and band
pass filters • External sound input

• Full size typewriter style design

• 66 Keys total • 2 Cursor control keys • 4 Function keys (up
to 8 user defined/programmable functions possible) • Upper and
lower case character set • Graphic character set

• User port • Serial port • ROM cartridge port • 2 Joystick/
paddle ports • Video port • C1 530 Cassette drive interface port

• Built-in BASIC 2.0— over 70 commands, statements and
functions • Full screen editor

• C1 541 Disk drive • C1530 Datasette •
printer • MPS 802 Dot matrix printer •

MPS 801 Dot matrix
MPS 803 Dot matrix
printer • DPS 1101 Daisey wheel printer • C1520
Plotter/Printer • C1 702 Color monitor • CM141 Color monitor

• 120 Volts, 60 Hz

Specifications subject to change without notice.

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PARTS LIST
C-64

Pi; Connectors) should be secured locally . Approved cross-references for TTL chips,
Transistors, etc. will be available in manual form through the Service Department in November

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fi*-^J ^'-3-i%#-'ft- ; ,-K: ■;

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TOP CASE ASSY

Top Case
Keyboard
LED Plate
Nameplate
Lamp Holder Set
LED Assembly

C
C
C
C
C
C

326113-01

326166-02

326160-01

326161-01

903820-03

1001039-01

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BOTTOM CASE ASSY

Bottom Case
Foot, Self-Adhesive
PCB Shield Plate
PCB Insulation Sheet

C 326114-01

C 950157-04

C 326131-01

C 326288-01

ACCESSORIES

Users Manual
Power Supply
RF Cable
Switch Box

C 320974

C 251053-02

C 326189-01

C 904778-01

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C-64 BLOCK DIAGRAM

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1 MEG
Hz<t>0

CASSETTE
PORT

<=JI

PADDLES

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RF
MOD

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SYNC

CHROMA

LUMA

6510
MICRO

1-
2-
3-
4-
5-
6-
7-

ADDRESS

DECODING

PLA

EXPANSION
PORT

DATA BUS

ADDRESS BUS

SID
CHIP

«*-7

"ir

MONITOR

6567

VIC

CHIP

--6

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BASIC

ROM

8K

KERNAL

ROM

8K

CHARACTER

GENERATOR

ROM

4K

64K ROM

USER
PORT

6526
CIA

KEYBOARD
MATRIX

^

CONTROL
PORTS

There are three versions of the C64. The C64 with a five pin connector video output (326106),
The C64 with an eight pin connector video output (251 1 38), and the C64B which has improved
system clock circuit design (251469). Most circuit theory explanations will be the same for all
three versions. Refer to schematic 326106 unless noted otherwise.

The Power Supply.

The external power supply generates a regulated 5VDC and 9VAC. 5VDC is applied to pins 5 and
1 of CN7 on the C64 pcb. Filtered by 1.5,097, and C100 it is then controlled by on/off switch S1 .
This 5VDC output supplies the microprocessor logic.

9VAC is applied to pins 6 and 7 of CN7 on the C64 pcb. + 1 2VDC, + 5VDC CAN and 9VDC unregulated
are outputs that are derived from this 9VAC supply. The 9VAC supply is made available on pins 10
and 1 1 of the USER PORT CN2.

12VDC Generation

9VAC is added to 9VDC through CR6, and rectified by CR5. The unregulated DC output is filtered
by C88 and C89 then regulated at 1 2VDC by VR1 . The regulated output is filtered by C57 and C59.
The 12VDC supplies the VIC and SID IC, and the audio amplifiers.

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C64 CIRCUIT THEORY

VR1

CMTl

5P1

+12 *-

rttF

ATKI

CKJT2

5P2

TCZ

+9 -—
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C5S ±. ±: C57
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- - 251V

M078I2GT

CR5

INJ40OI

-«F

C89=^C88
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- - 50V

PA 2

VRZ

PBQ

PBI

CAN +5

PBZ

PB3

CJ02>
.1

7805

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PB4

P65

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- ^ V - - 16V

PB6

PSlL

FLAG>£

.EESEi

^YAC^

SVAC^v/

5H1ELLD GND.

9 VAC

POWER INPUT CW7
(7- PIN MALE DIN)

+ 5VDC CAN Generation

9VAC is rectified by CR4. The unregulated DC output is filtered by C19, and C95 then regulated at
5VDC by VR2. The regulated output is filtered by C102 and C103. The output called 5VDC CAN
is separated and individually filtered into two outputs called Vvid and Vc. Vvid is the 5VDC supply
for the video circuits, and Vc is the 5VDC supply for the clock circuits.

9VDC Unregulated Generation.

CR4 rectifies the 9VAC input. The output is 9VDC unregulated. This supply powers the cassette motor
transistor amplifier circuits, and the RF modulator on the C64B version.

CAN +5 o-

Ftt

CG4_^
IO I

25V

CG3_
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50V "
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CAN +5 o-

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20%

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C64 CIRCUIT THEORY

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R34

47 K

25V JL

R5&1M
+ 5V o-AA/V

+5V

R3&
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Reset Logic Circuits.

U20 is a 556 IC timer configured as a one shot multivibrator. The output pulse width is determined
by the size of R34 and C24. Pulse width = 1 .1 x R34 x C24 « .5 seconds. The output on pin 9
is "high" active. The output of U8 is "low" active. Reset initializes all the processor logic and causes
the processor to load the program counter register with the address of the first instruction of the
operating system program called the KERNAL. The starting address is stored in locations $FFFC and
$FFFD. The first instruction is decoded and executed giving KERNAL control of the computer opera-
tions. The reset pulse occurs when turning the power on to the computer.

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+Vc

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C64 CIRCUIT THEORY

8.1816 MHt

* 5 - 2.7V

The C64 Clock Circuits.

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Crystal Y1 develops a 1 6MHz fundamental frequency clock signal. U31 is a Dual Voltage Controlled
Oscillator. The output on pin 10 is a 14.31818 MHz clock signal called the color clock. R27 can be
adjusted to obtain exact output frequency. U30 is a frequency divider that outputs a 2MHz signal
on pin 6. U29 is a D flip flop which outputs a 1 MHz signal on pin 9. U32 is a Phase/Frequency Detec-
tor which compares the output of the U29 to the phase clock, and outputs a dc voltage on pin
8 that is proportional to the phase difference between the inputs. The second half of the Dual Voltage
Controlled Oscillator U31 generates an 8.1818MHz clock signal called the DOT Clock. The VIC IC
divides the DOT clock by eight and outputs this as the phase clock on pin 1 7. The output of the
Phase/Frequency Detector is applied to the frequency control input pin 2 of U31 . This causes track-
ing of the dot clock and the color clock because one input, pin 3 of U32, is the phase clock which
is derived from the dot clock, and the other input pin 1 of U32, is derived from the color clock.

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87ot

-4 PAL

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— TIP— o tS

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-±-4\ U3I ^V. "

ii-, Yi- 77.73441 MHl- PAL Cl'tyf

V2

^hr Y

MTJC-

wcrtv

OP£A

- <?CQLQK) (/7. 7344 7 MHZ'PAU

V- ^#aZZk> ( 7.88 MHZ ' PAL)

The C64B Clock Circuits. Refer to schematic 251469

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Crystal Y1 develops the fundamental 1 6MHz clock signal. U31 is a Clock Generator IC that outputs
the 8.1818MHz DOT clock on pin 6, and the 14.31818 MHz color clock on pin 8.

6

C64 CIRCUIT THEORY

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CARTRIDGE / EXPANSION (44 -PIN FEMALE) CNG

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I/O and ROM Address Decoding and Expansion Port.

I/O Address Decoding Logic.

U17 is a Programmable logic array (PLA). The output F5 on pin 12 called I/O goes "low" when any
of the I/O devices controlled by U15 are selected. The addresses are listed below for each device.

VIC IC

$D000 ■

$D02E

SID IC

$D400 ■

$D7FF

Color Ram

$D800 -

$DBFF

CIA1

$DCOO ■

■ $DCOF

CIA2

$DDOO

- $DDOF

I/O 1

$DEOO -

$DEFF

I/O 2

$DFOO -

$DFFF

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ROM Address Decoding.

Basic ROM resides at locations $A000 - $BFFF. The output F1 pin 17 of the PLA U17 goes "low"
when the BASIC ROM is selected. The KERNAL ROM resides at locations $E000 - $FFFF. The output
F2 pin 16 of the PLA U17 goes "low" when the KERNAL ROM is selected. The CHARACTER
GENERATOR ROM resides at locations $D000 - $DFFF. The output F3 pin 15 of the PLA U17 goes
"low" when the Character Generator ROM is selected.

The Expansion Port Connections.

The expansion port is an extension of the microprocessor address, data, and control bus. ROML decodes
addresses $8000 - $9FFF, and ROMH decodes addresses $E000 - $FFFF. These are outputs from
the PLA used to select the cartridge inserted in the expansion port. I/O 1 input from U15 decodes
addresses $DE00 - $DEFF. I/O 2 output from U15 decodes addresses $DF00 - $DFFF.

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C64 CIRCUIT THEORY

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RAM Control Logic.

U1 3 and U25 are multiplexers. The address outputs from the microprocessor are passed to RAM via
U1 3 and U25 when the output Address Enable Control (AEC) from the VIC IC is "high". When AEC
is "low" the VIC IC outputs refresh addresses on pins 24 - 31 . AEC goes "low" when the system
clock, phase 2, is "low". Since all I/O decoding occurs when phase 2 is "high", refresh is transparent
to the processor.

Eight 41 64 DRAMS provide 64k bytes of memory. One 2114 RAM (U6) provides 512 bytes of memory
allocated for screen color data storage.

8

C64 CIRCUIT THEORY

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5 Pin Video and Audio Output Circuits.

Pin 1 5 of the VIC IC is the sync/luminance output. Pin 14 is the color output. A composite video out-
put is created by mixing sync/luminance and color. The composite output is applied to the RF modulator,
and also passed to the monitor connector CN5 on pin 4. The color output is not made available on
the monitor connector CN5 as on the 8 pin version, and the RF modulator mixes audio with the com-
posite video producing the TV RF output, unlike the 8 pin version RF modulator which creates the
composite video output.

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C64 CIRCUIT THEORY

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8 Pin Video and Audio Output Circuits. Refer to schematic 251469

U1 9 is the Video Interface Chip (VIC). Sync (horizontal and vertical), and luminance (video) is output
on pin 1 5. This signal is passed to pin 2 of the RF modulator. Color is output on pin 14, and passed
to pin 3 of the modulator. Light Pen inputs are sensed by the VIC IC on pin 9. U1 8 is the Sound Inter-
face Device IC (SID). The audio output is on pin 27, and audio input is on pin 26. The RF modulator
mixes sync/luminance, color, and audio out, generating a TV composite signal on pin 2. The RF
modulator also passes the VIC outputs to the monitor connector CN5. Audio out on pin 27 is amplified
by Q2, and output on pin 3 of CN5. Audio in is applied to pin 5 of CN5, then to pin 26 of the SID
IC. Inputs from paddles connected to one of the control ports are monitored by the SID IC on pins
23 and 24.

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C64 CIRCUIT THEORY

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PAG G52G

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PBO (DCOO-

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PB2

PB3

PB4

PB5

PB6

PB7

CNT

SP

D7
DC
05
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D3
02
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DO

RS3
R52
RSI
RSD
IRQ

RS

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TOD 6K|D

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The Cassette Interface Circuits.

U7 is a 6510 microprocessor. One of the features of the 6510 is a built in parallel I/O port (P0-P5).
P3 - P5 control most of the cassette interface circuitry. P3 pin 26 of U7 outputs the write data signal
to connector CN3 on pins E and 5. P4 is an input that senses the play switch depressed on the cassette
deck. P5 is an output that controls the cassette motor. When P5 goes "low", Q2 cuts off, CR2 regulates
Vb of Q1 at 7.5 volts, this forward biases Q1 and Q3, passing current through the cassette motor
coil. U1 is a Complex Interface Adapter (CIA). Parallel ports, serial outputs, and Timers are standard
features of the CIA. Read data enters on pins D, 4 of CN3. U1 accepts the read data signal on the
FLAG input pin 24.

11

C64 CIRCUIT THEORY

K

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1

2

7

4

5

6

,3

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1

**

CTRL

STOP

SPACE

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Q

2

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W

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SHIFT

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CLR

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DEL

RET

CRSR

A
CRSR

f

F1

F3

F5

F7

L_

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U20

NMI 6510

RESTORE

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555

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CARTRIDGE EXPANSION
CNG

KEYBOARD MATRIX

Keyboard, Joystick, and Paddle Interface Circuits.

Keyboard Interface.

U1 is a Complex Interface Adapter (CIA). Both parallel ports are used to decode the keyswitches on
the keyboard. Parallel port A signals (PAO - PA7) are outputs. Parallel port B signals (PBO - PB7) are
inputs. A "0" bit is shifted through the parallel port A, when a key is depressed on the keyboard,
the "0" bit is returned on one of the parallel port B inputs. A program in the KERNAL ROM generates
the shifting "0" bit output on parallel port A, and decodes the signals returning on the parallel port
B inputs. Depressing the restore key causes U20 to trigger. U8 pin 6 goes "low" generating a Non-
Maskable Interrupt (NMI) at the processor. This causes the processor to execute a subroutine which
initializes the I/O Interfaces. If the STOP key is depressed at the same time, BASIC flags are also
initialized.

Joystick Interface.

U1 also controls the joystick. Parallel port A accepts inputs from the B joystick connected to control
port 2. Parallel port B accepts inputs from the A joystick connected to control port 1 . When the joystick
is moved up, down, left, right, or the fire button is depressed, a ground potential is applied to the
appropriate input of U1.

Paddle Interface.

A Variable resistor is connected to adjusting knob on the paddle. When the knob is rotated, the
resistance varies controlling the time constant of an RC network. The Voltage developed across the
capacitor is input to an A/D converter internal to the SID chip U18. The digital output is stored in
one of the SID registers. The paddle position can be determined by the reading the contents of the
appropriate register. U28 is a 4066 CMOS switch. The signals from the paddles are passed to the
SID chip when the Enable inputs (EO - E3) of U28 are "high".

NOTE: U1 port assignments are incorrect on
schematics. Refer to Keyboard Matrix
for correct assignments.

12

C64 CIRCUIT THEORY

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tcz

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CNT2

R30f-Wv — tf I -=

IK L-AAA, » 1 ^3

— (DCOO-
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-§P83

rs, SL-JJ-
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■ P A? ...

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PB2

-P- fia

PB4

P65

Pflfe

flfcl

RESET

^ +!

%VAC^

The Serial Interface and User Port Circuits.

The Serial Interface.

U2 is a Complex Interface Adapter (CIA). Parallel port signals PA3-PA7 control the serial bus inter-
face. PA3 is the Attention (ATN) output. This signal is inverted by U8 before being transmitted to
a device on the bus. PA4 is the Clock output. Data transmitted from the C64 to a device on the bus
is synchronized by this clock signal. U8 inverts the output PA4. PA5 is the data output. U8 inverts
this output also. Data transmitted from a device on the bus to the C64 is synchronized by a clock
generated by the transmitting device. The Clock signal is input on PA6. Data transmitted from a device
on the bus to the C64 is input on PA7. When a device on the bus wants to communicate with the
C64, SRQ IN goes "low" indicating service is requested.

The User Port.

Parallel port B of U2 (PBO - PB7) is made available on the user port. Parallel data transfers with exter-
nal devices are made very easily through this parallel port. SP2 and SP1 are bi-directional serial ports.
CNT1 and CNT2 are bi-directional synchronizing clock signals for each serial port.

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13

64 TROUBLESHOOTING GUIDE

SYMPTOM

POSSIBLE SOLUTION

Blank screen on power up.

Check External Power Supply

U4 (KERNAL ROM), U17 (PLA)
U7 (6510 MPU), U3 (ROM)
U8 (7406 IC), U19 (VIC II)
U9-U12 (4164 RAM)
U21-U24 (4164 RAM)
VR2, CR4, VR1

Out of memory error on power up.

Check U9-U 12 (4164 RAM)

U21-U24 (4164 RAM)
**** USE DIAGNOSTIC TEST - DISK

No cursor displayed.
Intermittent blank screen.

Check U1, U15, U7
Check U2, U7

Powers up with graphic display and
blinking cursor.

Check U1 4 (74LS258 IC)

Powers up with all the characters
displayed as blocks.

Check U26 (74LS373 IC)

Intermittent display.

Check C88 (Possible Bad Connection)

Powers up with TRESS PLAY ON
TAPE' message and the display blanks.

Check U7 (6510 MPU)

R1 (Possible Bad Connection)

On power up the cursor locks up.

Check U7 (6510 MPU)
U20 (556 IC)

When 'RETURN' is pressed after a run
command, the cursor goes back to
home position.

Check U3 (ROM)

Poke command does not work.

Check U3 (ROM)

Joystick does not operate correctly.

Check U1, U28 (6526 CIA)

Wrong frequency.

Check C70

No character lettering is displayed on
the screen.

Check U3 (ROM)
U2 (CIA)

Graphic characters instead of letters
displayed.

Check U19 (VIC II)

Power up message appears but no

Check U1, U15, U7 and U4

cursor.

14

64 TROUBLESHOOTING GUIDE (Continued)

n

r\

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SYMPTOM

POSSIBLE SOLUTION

Cursor jumps back to home position.

Check U7 (6510 MPU)

Abnormal colors appear in the letters.

Check U6 (2114 RAM)
U16 (4066 IC)

Different characters are displayed and
cursor is locked when turned on and
off.

Check RAM

System does not reset and the
'RESTORE' key does not work.

Check U20 (556 IC)

White band scrolls down the screen.
(60 HZ HUM)

Check External Power Supply
VR2 (5V Regulator)

Cursor disappears after the system
warms up.

Check U1 (6526 CIA)

SYNTAX ERROR displayed after
system warms up.

Check RAM, U3 (ROM)

Wavy screen after the system warms
up.

Check External Power Supply
U31 (74LS629 IC)
U30 (74LS193 IC)

The system resets when it warms up
and long programs do not load.

Check U7 (6510 MPU)
U3 (ROM)

Keyboard does not operate correctly
when the system warms up.

Check U1 (6526 CIA)
U3 (ROM)

Black band scrolls through screen
when system warms up.

Check External Power Supply
C90, C88, CR4
VR2 (5V Regulator)

Cassette motor keeps running.

Check U7 (6510 MPU)

Cassette motor keeps running even
after a program is done loading. The
TIP 29 transistor gets extremely hot
and the fuse may possibly blow.

Check Cassette Port for Shorts
R4 (Possibly Open)

The cursor disappears when the
cassette is plugged in.

Check U7 (6510 MPU)

Cassette runs extremely slow. The
program seems to load but will not
run.

Check U7 (6510 MPU)

15

64 TROUBLESHOOTING GUIDE (Continued)

n

SYMPTOM

POSSIBLE SOLUTION

When loading from a cassette, the
'SYNTAX ERROR' message is
displayed.

Check U20 (556 IC)

DEVICE NOT PRESENT ERROR is
displayed when disk is used.

Check U1 (6526 CIA)
U7 (6510 MPU)
R28, R29, R30

Disk drives continue to search when
trying to load.

Check U2 (6526 CIA)

When loading from disk and any key of
the 4th row of the keyboard is
pressed, the cursor goes to home
position.

Check U20 (556 IC)

R35 (Possible Bad Connection)

When loading from disk, a 'FILE NOT
FOUND' message is displayed.

Check U4 (ROM)

U2 (6526 CIA)

OUT OF MEMORY ERROR is displayed
when disk is used.

Check U20 (556 IC)

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16

C64 BOARD IDENTIFICATION

n

To date there are 4 versions of 64 PCB assemblies in use.

n

VERSION

IDENTIFYING FACTORS

Original

5 pin board
(CN5-Video port has 5 pins)

A (CR)

8 pin board
(CN5-Video port has 8 pins)

B

8 pin board
(Reduced oscillator circuit)

B-2

8 pin board
(Reduced Osc. w/component changes)

PCB ASSY # SCHEMATIC #

326298-01 326106

250407-04

250425

250441-01*

251138

251469

251469

n

— These boards are interchangeable with casework, keyboard, etc.; however, care must be taken
to provide the customer with a unit that is compatible with their monitor and cable.

— When component level repairs are necessary, be certain to acquire the appropriate part for the
board you are repairing. Most modulators are different, as are many of the other components.

*The 4th version of 64 board was recently developed and only a few may be in the field. It is termed
the 64B-2. All circuits remain the same as the 64B (Schematic 251469) with a few component loca-
tion changes:

1) Resistors 28, 29, 30, 36, 48 were reduced to Resistor Pack RP5.

2) Diodes CR100-105 are no longer piggybacked. Their new locations are CR9, 12-16.

17

n

D

n

o

I

00
0)
M
(O
<M
CO

o
>

<

<
o

18

PARTS LIST - PCB ASSEMBLY #326298
C — Indicates Commodore Stocked Part Numbers

INTEGRATED CIRCUITS

RESISTORS (Continued)

U1,U2

6526 CIA

C 906108-01

R14

100

R30

1K

U3

2364 Basic ROM

C 901226-01

R16

1K

R31

180

U4

2364 Kernal ROM

C 901227-03

R17

1.2K

R33

47K

U5

2332 Char ROM

C 901225-01

R19

15K

R34

47K

U6

2114L-30 RAM

901453-01

R20

6.8K

R35

470K

U7

6510 ft, Processor

C 906107-01

R21

4.7K

R37

2.7K

U8

7406

901522-06

R22

1.5K

R38

1K

U9-U12

4164 (200 nS)

901 505-01

R23

1K

R39

390

U13

74LS257

901521-57

R24

3.3K

R41

1M

U14

74LS258

901521-58

R25

Pot 1K

R43

3.3K

U15

74LS139

901521-18

R26

75

R44

3.3K

U16

4066

901502-01

R27

Pot 2K

R45

3.3K

U17

82S100 PLA

C 906114-01

R28

1K

R46

2K

U18

6581 SID

^\ ^ ^\ ^ f \ /l^^ II

C 906112-01

R29

1K

R51

1.5K

U19

U20

U21-U24

U25

U26

6567 VIC II

LM556

4164 (200 nS)

74LS257

74LS373

C 906109-01
901523-03
901505-01
901521-57
901521-29

NOTE: The input video line requires a 470 ohm,
1/4 watt, resistor soldered to ground.

RESISTOR PACKS

U27

# 1 ImWW / ^^

74LS08

901521-03

RP1,2

33Q, 8 Pin (Bourns No.

U28

4066

901502-01

4308R- 102-330)

U29

74LS74

901521-06

RP3

3.3KQ, 8 Pin (Bourns No.

U30

74LS193

901521-26

4308R-101-332)

U31
U32

74LS629
MC4044

901521-68
906128-01

RP4

3.3KQ, 10 Pin

CAPACITORS

TRANSIS

roRS

C1-3

Ceramic .1 /tF, 50V

Q1

2N4401

902652-01

C4-7

Ceramic .47 /tF, 50V, 20%

Q2

2N3904

902658-01

C8

Electrolytic 10 /tF, 25V, +50%, -10%

Q3

TIP29 B

902653-01

C9

Ceramic .47 /tF, 50V, 20%

Q4-8

2N2222

902686-01

C10,11
C12-15

Ceramic 470 pF, 50V

Electrolytic 10/tF, 25V, +50%, -10%

DIODES

C16
C17
C18
C19

Ceramic .1 /tF, 50V

Electrolytic . 10 /tF, 25V, +50%, -10%

Ceramic .1 /tF, 50V

Electrolytic 2200 /tF, 1 6V

CR1
CR2
CR3

2.7V Zener IN4371
7.5V Zener IN755
IN914

CR4
CR5,6

Bridge, Varo VM08
Rectifier IN4001

906129-01

C20,21

C22

C23

Film .22 /tF, 100V, 20%

Ceramic .1 /tF, 50V

Ceramic 360 pF, 50V

Electrolytic 10 /tF, 25V, +50%, -10%

RESISTOI

SS — All values are in ohms- 1/4 W,

C24

5%, unless noted otherwise.

C25-28

Ceramic .22 /tF, 50V

C29

Ceramic .47 /tF, 50V, 20%

R1

3.3K

R7

10K

C30,31,32

Ceramic .1 /tF, 50V

R2

1.5K

R8

390

C33

Ceramic .47 /tF, 50V, 20%

R3

10K

R9

75

C34

Electrolytic 10 /tF, 25V, +50%, -10%

R4

1K

R10

120

C35

Ceramic .1 /tF, 50V

R5

560

R11

120

C36

Ceramic 20 pF, 50V

R6

1K

R13

1K

C37

Ceramic 1000 pF, 50V

19

PARTS LIST - PCB ASSEMBLY #326298 (Continued)
C — Indicates Commodore Stocked Part Numbers

n

n

n

CAPACITORS (Continued)

CAPACITORS (Continued)

C38

Ceramic

51 pF, 50V

C94

Electrolytic 10 /tF, 25V,

+ 50%, -10%

C39

Ceramic

.1 /tF, 50V

C95,96

Ceramic .1 /tF, 50V

C40-43

Ceramic

.22 /tF, 50V

C97

Ceramic .22 /tF, 25V

C44

Ceramic

.47 /iF, 50V, 20%

C98,99

Ceramic .1 /tF, 50V,

20%

C45,46,47

Ceramic

.1 iiF, 50V

C100

Ceramic .22 /tF, 25V

C48

Ceramic

1800 pF, 50V

C101

Ceramic .1 /tF, 50V,

20%

C49

Ceramic

470 pF, 50V

C102

Electrolytic 10 /tF, 25V,

+ 50%, -10%

C50

Ceramic

.22 /tF, 50V

C103

Ceramic .1 /tF, 50V

C51

Ceramic

.47 ixF, 50V, 20%

C105

Ceramic .1 /tF, 50V

C52.53

Ceramic

470 pF, 50V

C54
C55
C56

Ceramic
Ceramic
Ceramic

.22 /tF, 50V
.1 /tF, 50V
.1 iiF, 50V
10 pJF, 25V, +50%,
-10%

CONNECTORS

CN1

Header Assy, 20 Pin

903331-20

C57

Electrolytic

CN4
CN5

6 Pin Din
5 Pin Din

C 903361-01
C 903362-01

C58

Ceramic

.1 /tF, 50V

CN6
CN7

44 Pin Card Edge
7 Pin Din

C 906100-02
C 906130-01

C59

C60,61

C62

Ceramic
Ceramic
Electrolytic

.22 /iF, 50V
.47 iiF, 50V, 20%
10 iiF, 25V, +50%,

CN8,9
CN10

Plug Assy, 9 Pin Rt. Angle
Header Assy, 3 Pin

C 906126-01

C63

Ceramic

-10%
.47 nF, 50V, 20%

MISCELLANEOUS

C64,65

Electrolytic

10 /tF, 25V, +50%,

L1,2

Coil Inductor 2.2 /tH

901151-17

-10%

L3

Coil Inductor 3.0 /tH

901151-21

C66.67

Ceramic

.47 /tF, 50V, 20%

L4

Line Filter Assy

C 906127-01

C68

Ceramic

.1 /tF, 50V

L5

Coil Inductor 1 .2 /tH

901152-01

C69

C70

Mica

10 pF, 500V, 5%

Y1

Crystal 14.31818 MHz

C 900558-01

C71

Ceramic

.1 /tF, 50V

C72

Ceramic

220 pF, 50V

SW1

Rocker Switch DPDT

C 904500-01

C73
C74

Ceramic
Ceramic

1 50 pF, 50V
.1 /tF, 50V

VR1

Voltage Regulator
MC7812CT

901527-01

C77
C78

Ceramic
Ceramic

.1 /tF, 50V
220 pF, 50V

VR2

Voltage Regulator
MC7805CT

901527-02

C79

Ceramic

510 pF, 50V

C80

Ceramic

51 pF, 50V

M1

Modulator

C 326130-01

C81

Ceramic

20 pF, 50V

C82

Ceramic

.1 /tF, 50V

F1

Fuse, Normal Bio, 250V, 1.5A

C83

Mica

33 pF, 500V, 5%

C84

Ceramic

.1 /tF, 50V

FB1-23

Ferrite Bead

903025-01

C85

Ceramic

.47 /tF, 50V, 20%

C86

Mica

39 pF, 500V, 5%

Connector Panel

C87

Ceramic

.1 /tF, 50V

(ON, OFF, Joystick)

326299-01

C88

Electrolytic

470 /tF, 50V

Cartridge Guide

326116-01

C89

Ceramic

.1 /tF, 50V

Shield Box

C 326265-01

C90

Electrolytic

470 /tF, 50V

Shield Cap

C 326267-01

C91

Electrolytic

100 /tF, 16V

C92

Ceramic

.22 /tF, 50V

C93

Ceramic

1800 pF, 50V

20

SCHEMATIC #326106 SHEET 1 OF 2

LI I.ZajW

:CG3zt rbc&l

± 1.47

50V
20%

1 ^^^ r

^_ C(c7

— 5DV '
20«fc

I. VC SHOULD BE USED TO DRIVE ONLY DEVICES
NDICATED.
'2.YI-I4.3I6I6 MHZ -NTSC
17.734472 MH2- PAL

3. ALL RESISTORS ARE I/4 WATT+5% UNLESS
OTHERWISE SPECIFIED.

4. ALL CAPACITOR VALUES ARE IN
UNLESS OTHERWISE SPECIFIED.

5. CAP,50PF: ONLY WITH R4 OR R4T2 VERSIONS
OF 6567.

6. SEE ECO NO. 2096 TOR INSTRUCTIONS OK)
OF Ct06 .
T. CAP, 220PF: OJLy WITH Rl VERSION OF 6569.

POWER TNPUT CN7
(7- PIN MALE DIN)

21

PIN
CONFIGURATION

U9 ~ 12, U21 ~ 24

64K DYNAMIC RAM

901 505-01

COMMODORE

PART

NUMBER

APPROVED
SOURCE 1
OF SUPPLY

VENDOR

PART
NUMBER

ACCESS
TIME

(ns)

CYCLES

(ns)

POWER

ACTIVE

(MW)

STANDBY
(MAXMMW)

901505-01

HITACHI

HM4864-3

200

335

330

20

901505-01

NEC

/tPD4 164-2

200

375

250

28

901505-01

MITSUBISHI

M5K416NS-20

200

330

275

28

901505-01

MOSTEK

MK4564N-20

200

345

300

22

901505-01

OKI

MSM3764-20

200

330

248

23

901505-01

HITACHI

HM4864P-3

200

335

330

20

901505-01

MATSUSHITA
(PANASONIC)

MN4164P-20

200

330

275

27.5

901505-01

SIEMENS

HYB4164-3

200

330

150

20

901505-01

SHARP

LH2164-Z1

200

330

248

28

901505-01

HITACHI

HM4864AP-3

200

330

242

20

901505-01

TOSHIBA

TMM4164AP-20

200

330

275

22

WE

RAS<

CAS

R/W CLOCK
GENERATOR

RAS CLOCK
GENERATOR

CAS CLOCK
GENERATOR

(/>
in
(/>

(/>

UJ

OC
Q

a
<

x
c/>

UJ

u.

UJ

OC

A7o
( A6o—

AO

(/>

OC
UJ

u.

LL
D
00

</>

(/>

UJ

OC
D
Q
<

-^Hl

^1

R/W SWITCH

MEMORY
ARRAY

ROW DEC

C=> C=C>ROW DEC.

MEMORY
ARRAY

MEMORY
ARRAY

ROW PEC- ^3 c=£>

MEMORY
ARRAY

u

MEMORY
ARRAY

MEMORY
ARRAY

MEMORY
ARRAY

ROW DEC

MEMORY
ARRAY

4h4

DATA IN
BUFFER

DATA OUT
BUFFER

-oDIN

-oDOUT

-oVCC
^>VSS

VBB GENERATOR

FUNCTIONAL DIAGRAM

SCHEMATIC #326106 SHEET 2 OF 2

ANDBY
!VX)(MW)

20
28
28

22

23

20

27.5

20

28

20

22

r +V RF Ml —

* - VIC 4 SID SHOULD HAVE

SEPARATE GND RETURM5.

^ - LC ^ ; f 17.73447 2 MM 2 - PAL)

DffTCLDCK) i 6 - 18 ^ H * ' MT5C)
^(7-88 MH&- PAL)

CARTRIDGE / EXPANSION (44 -PIN FEMALE) CNG

22

MODULATOR SCHEMATIC #251025

COLOR IN a

LUMI INO

GROUND

AUDIO IN a

+ B O

INTER CARRIER
SELECTORO

O COLOR OUT

NOTE

1.Q1^Q3 :2SC1684 OR EQlVALENT
2.04 :2SC173O0R EQIVALEN T
IQ5 '.2SC460 O R EQIVALENT
4.Q6 :2SC2120 OR EQIVALENT
501 ;H2-7 02.D3.1SS119

6, ALL C A PAC I TAN CE VA L UES J

7.ALL RESISTANCE VALUE S :H
a A 11 I NDUCTANCE VALUES :H

RE OUT

UMd.H4*Li

7^

ili^^-i

//*

M/iJ

^ r

1

77

I j-is! .

i

56

*

»-*

«0

h '

U

i

<

>-

tt

d

Hfllt

1, R£CQMMEND£P RC.B. HOLE CENTERS

2.ALL DIMENSION ARE IN MILLITER?
3. N08TERM1 NAL SH0RT*(LPAI

n

Nl
35!

SI
\

55|

n

n

i

fi

hi

S§i8

O

o
o

CM

3
O

>
<

<

o

23

PARTS LIST - PCB ASSEMBLY #250407-04
C — Indicates Commodore Stocked Part Number

n

n

INTEGRATED CIRCUITS

U1,U2

U3

U4

U5

U6

U7

U8

U9-U12

U13

U14

U15

U16

U17

U18

U19

U20

U21-U24

U25

U26

U27

U28

U29

U30

U31

U32

6526 CIA

2364 Basic ROM

2364 Kernal ROM

2332 Char ROM

2114L-20 RAM

6510 /t Processor

7406

7416

4164 (200 nS)

74LS257

74LS258

74LS139

4066

82S100 PLA

6581 SID

6567 VIC II

LM556

4164 (200 nS)

74LS257

74LS373

74LS08

4066

74LS74

74LS193

74LS629

MC4044

C 906108-01

C 901226-01

C 901227-03

C 901225-01

901453-01

C 906107-01

901522-06 sub:

901522-14

901505-01

901521-57

901521-58

901521-18

901502-01

C 906114-01

C 906112-01

C 906109-01

901 523-03

901505-01

901521-57

901521-29

901521-03

901502-01

901521-06

901521-26

901521-68

906128-01

TRANSISTORS

Q1,2

Q3

Q7,8

2SC1815
TIP29 A
2SC1815

C 902693-01 sub:

902653-01

C 902693-01

DIODES

CR1
CR2
CR4

CR5,6

2.7V Zener IN4371
7.5V Zener IN755
Bridge S2VB10 3D
DBA20B
DBA20C
Rectifier IN4001

906103-02

900941-01

C 251026-01

C 251026-02

C 251026-03

900750-01

RESISTORS — All values are in ohms- 1 /4 W,
5%, unless noted otherwise.

R1
R2
R3
R4
R5

n

3.3K

1.5K

10K

1K

560

R6

RR7

R16

R17

R19

1K

10K

1K

2.7K

15K

RESISTORS (Continued)

R26
R27
R28
R29
R30
R31
R33
R34
R35
R36
R37
R38

Jumper Wire

Pot 5000

1K

1K

1K

180

47K

47K

470K

1K

2.7K

1K

R39

R41

R42

R43

R44

R45

R50

R51

R52

R53

R100

R101

390

1M

82

3.3K

3.3K

3.3K

1M

1.5K

300

390

1K

22K

RESISTOR PACKS

RP1,2

RP3

RP4

330, 8 Pin (Bourns No.
4308R- 102-330)
3.3KG, 8 Pin (Bourns No.
4308R-101-332)
3.3KQ, 10 Pin

CAPACITORS

C1-7

C8

C9

C10,11

C12

C13,14,15

C16

C17

C18

C19

C20,21

C22

C23

C24

C25-33

C34

C35

C36

C37

C38

C39-47

C48

C49-54

C55

C56

C57

C58

Ceramic .1 /tF, 25V

Electrolytic 10 /tF, 25V, +50%, -10%

Ceramic .1 /tF, 25V

Ceramic 470 pF, 50V, 10%

Ceramic .1 /iF, 25V

Electrolytic 10 /tF, 25V, +50%, -10%

Ceramic .1 /tF, 25V

Electrolytic 10 /tF, 25V, +50%, -10%

Ceramic .1 /tF, 25V

Electrolytic 2200 /tF, 1 6V

Film .22 /tF, 100V, 20%

Ceramic .1 /tF, 25V

Ceramic 360 pF, 50V, 10%

Electrolytic 10 /tF, 25V, +50%, -10%

Ceramic .1 /tF, 25V

Electrolytic 10 /tF, 25V, +50%, -10%

Ceramic .1 /tF, 50V

Ceramic 20 pF, 50V, 5% SL

Ceramic 1000 pF, 50V, 10% B

Ceramic 51 pF, 50V, 5% SL

Ceramic .1 /tF, 25V

Ceramic 1800 pF, 50V, 10% B

Ceramic .1 /tF, 25V

Ceramic .1 /tF, 50V

Ceramic .1 /tF, 25V

Electrolytic 10 /tF, 25V, +50%, -10%

Ceramic .1 /tF, 50V

24

PARTS LIST - PCB ASSEMBLY #250407-04 (Continued)
C — Indicates Commodore Stocked Part Number

s~\

n

CAPACITORS (Continued)

CONNECTORS

C59,60

Ceramic

.1 /tF, 25V

CN1

Header Assy, 20 Pin

903331-20

C62.65

Electrolytic

10 /tF, 25V,

+ 50%,

CN4

6 Pin Din

C 903361-01

-10%

CN5

8 Pin Din

C 325573-01

C66,67,68

Ceramic

.1 /tF, 25V

CN6

44 Pin Card Edge

C 906100-02

C70

Film

16 pF, 5%

CN7

7 Pin Din

C 251116-01

C74,82

Ceramic

.1 /tF, 25V

CN8.9

Plug Assy, 9 Pin MINID

C 906126-01

C83

Ceramic

82 pF, 5%

CN10

Header Assy, 3 Pin

903332-03

C84

Ceramic

.1 /tF, 25V

C85
C88
C89
C90
C91

Ceramic

Electrolytic

Ceramic

Electrolytic

Electrolytic

.47 /tF, 50V,

1000 /tF, 25V

.1 /tF, 25V

470 /tF, 50V

100 /tF, 16V,

10%
+ 50%,

MISCELLANEOUS

L2
L4
L5

Coil Inductor 2.2 /tH
Coil Inductor 1 .2 /tH
Choke Coil

901151-17

325570-01

C 325559-02

-10%

Y1

Crystal 14.31818 MHz

C 900558-01

C92

Ceramic

.1 /tF, 25V

C93

Ceramic

1800 pF, 50V,

10% B

SW1

Rocker Switch DPDT

904500-01

C94

Electrolytic

10 /tF, 25V,
-10%

+ 50%,

VR1

Voltage Regulator

C95.96

Ceramic

.1 /tF, 25V

MC7812CT

901527-01

C97

Ceramic

.22 /tF, 25V

VR2

Voltage Regulator

C98,99

Ceramic

.1 /tF, 50V,
-20%

+ 80%,

MC7805CT

901 527-02

C100

Ceramic

.22 /tF, 25V

M1

Modulator

C 251080-01

C101

Ceramic

.1 /tF, 50V,

+ 80%,

-20%

F1

Fuse, Normal Bio, 250V,

1.5A

C102

Electrolytic

10 /tF, 25V,

+ 50%,

-10%

FB1-5

Ferrite Bead

903025-01

C103

Ceramic

.1 /tF, 25V

FB7-23

C104

C105

Ceramic

.1 /tF, 25V
10 /tF, 25V,
.1 /tF, 25V

Connector Panel

C108
C200

Electrolytic
Ceramic

20%

(Power, ON, OFF)
Cartridge Guide

251095-01
326116-01

Shield Box

C 251023-01

Shield Cap

C 251024-01

n

25

U1, U2 - 906108-01

6526 COMPLEX INTERFACE

ADAPTER (CIA)

PIN
ASSIGNMENT

GND-
PAO-
PA1-
PA2-
PA3-
PA4-
PA5-
PA6-
PA7-
PBO-
PB1-
PB2-
PB3-
PB4-
PB5-
PB6-
PB7-
PC-
TOD-
VCC-

1

40

2

39

3

38

4

37

5

36

6

35

7

34

8

33

9

32

10

31

11

30

12

29

13

28

14

27

15

26

16

25

17

24

18

23

19

22

20

21

-CNT

-SP

-RSO
RS1
RS2

-RS3

-FLAG
CS_
- R/W
-IRQ

1 VSS

2-9 PA0-PA7

10-17 PB0-PB7

18 PC

TOD

Bidirectional parallel
Bidirectional parallel
low pulse is

19

20
21

22

VCC
IRQ

R/W

RES

DBO

23

CS

DB1
DB2

24

FLAG

DB3

DB4
DB5

25

02

DB6
DB7

26-33

DB0-DB7

02

34

RES

35-38 RS0-RS3

39

40

SP

CNT

Ground Connection.
Parallel port a signals
port.

Parallel port b signals
port.

Handshake output. A
generated after a read or write on port b.
Time of day clock input. Programmable
50hz or 60hz input.
5VDC input.

Interrupt output to microprocessor input
IRQ.

READ/WRITE input from microprocessor's
R/W output.

Chip select input. A low pulse will ac-
tivate CIA.

Negative edge sensitive interrupt input.
Can be used as a handshake line for
either parallel port.

02 clock input. Connected to processor
common 02 clock.

Bidirectional data bus. Connects to pro-
cessor data bus.

Low active reset input. Initializes CIA.
Register select inputs. Used to select all
internal registers for communications with
the parallel ports, time of day clock, and
serial port (SP).

Serial Port bidirectional connection. An in-
ternal shift register converts micropro-
cessor parallel data into serial data, and
visa-versa.

Count input. Internal timers can count
pulses applied to this input. Can be used
for frequency dependent operations.

U18 - 906112-01

6581 SOUND INTERFACE

DEVICE (SID)

PIN
ASSIGNMENT

CAP-

1A

28

CAP-

1B

27

CAP-

2A

26

CAP-

2B

25

RE5-

5

24

02-

6

23

R/W-

7

22

CS-

8

21

A0-

9

20

A1-

10

19

A2-

11

18

A3-

12

17

A4-

13

16

GND-

14

15

1,2,
3,4
5

CAP1A,1B
2A, 2B
RES

-12V

-A. OUT

-EXT IN

-5V

-POT X

-POT Y

-D7

-D6

-D5

-D4

-D3

-D2

-D1

-DO

6

02

7

R/W

8

CS

9-13

A0-A4

14

GND

15-22

D0-D7

23

POT Y

24
25
26
27

28

POT X
VCC
EXT IN
Audio out

Vdd

Capacitor filter connections.

Reset input. A low pulse initializes the

SID.

Processor phase 2 clock input.

Processor read/write input.

Chip select input.

Address lines from processor.

Dc ground connection.

Data Bus connections.

Input to a A/D converter used to detect

the value of a variable resistor. Commonly

connected to game paddles.

Same as POT Y.

5VDC.

External audio input.

Audio output. Should be AC coupled to

audio amp.

12VDC.

SCHEMATIC #251138 SHEET 1 OF 2

(V0-D7> -

cw>

(A0-Af5> ~

<JARAM> -

JHIRAH> -

KTCi

pKfc

[AS a % 4 w

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6j\ti

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^ RP1

MA7

4a*\^ww<

74LS0B

(VA(4 >
( /P/VV> -

C^7U^

74LS06

ghii>-

,./ A/C-

^W^^2

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RP4

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Vfc

1//2

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4/44-2

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4/64-2
RAM

f£Z ±i W J£

8

W&

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m

UtSUUl

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3* 2

-iff 411

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wuieptaita

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Vap 23L4A
±% KERNAL
*A5 KOM
f & (E000-

%% FFFF)

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§ 5?5fe|g^J

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ysiiP&

,0iMHl-NT3C)
.98MHM - *4£ )

- Q7M4/tE)

i

■NOTES

MM

COLOR

AOD

MC-

AUD
2UL

m

Q
Uj

k

a

03

o
o

-<KQU£)

(f4.3/Bf8MHB-MTSC )
f/7. 734472MH*- P*L )

(8J8MHt-NTSC)
C 7.96MN*-PAL)

^// 7

ceo 3

c^oa

/?<^

u

7700-00f

—

—

oa sl

7700- QOt

*92PF±$%$L

—

aea

HBmA/Ot

6ZPF±S%SL

82 a

i'/F CASE 6569 RZV3 FOR U 1<? ,
DO NT]' USE IMS CAPfiClTORV
¥- VIC $ SID SHOULD HAVE SEPARATE

€fND RETURNS .
b. U19 = ^67 (NTSC)
= 6569 (PAL)
NOTES -UNLESS OTHERW/SE ^PECfFjEB \

CARTRIDGE/ EXPANSION (44 PIN FEMALE ) CNi

26

PIN
ASSIGNMENT

Q1-

RDY-

IRQ -

NMI-

AEC-

VCC-

AO-

A1-

A2-

A3-

A4-

A5-

A6-

A7-

A8-

A9-

A10-

A11-

A12-

A13-

1

40

2

39

3

38

4

37

5

36

6

35

7

34

8

33

9

32

10

31

11

30

12

29

13

28

14

27

15

26

16

25

17

24

18

23

19

22

20

21

-RES

-02_

-R/W

-DBO

-DB1

-DB2

-DB3

-DB4

-DB5

-DB6

-DB7

-PO

-P1

-P2

-P3

-P4

-P5

-A15

-A14

-GND

PIN
ASSIGNMENT

PE + -I
17-
16-
15-
l 4 -
13-
12-

n-

io-

F7-

F6-

F5"
F 4 -

GND-

1

28

2

27

3

26

4

25

5

24

6

23

7

22

8

21

9

20

10

19

11

18

12

17

13

16

14

15

h v cc

8

9

10

11

12

13

14

15
-CE

-FO
F1
F2
F3

U17 - 906114-01

PROGRAMMABLE

LOGIC ARRAY (PLA)

U7 - 906107-01
6510 MICROPROCESSOR

1 01 Phase 1 clock input. This clock input is

used to develop the internal overlapping
phase 2 clock. 1 MegHz or 2 MegHz
speeds.

2 RDY Single step operation input. A low applied

will cause the processor to halt. The cur-
rent address line being fetched will be on
the address bus. Can also be used to in-
terface slower devices to the micropro-
cessor.

3 IRQ Interrupt request input. When a low pulse

is applied a jump to a location specified
by the contents of FFFE and FFFF will oc-
cur to service the interrupt, if the interrupt
mask flag is not set. This is a maskable
interrupt.

4 NMI Non-maskable interrupt input. A low tran-

sition will cause a jump to a location
specified by FFFA and FFFB to a subrou-
tine which will service the interrupt.

5 AEC Address enable control input. A low ap-

plied to will cause the address bus to
enter hi impedance state, so other devices
can control the address bus.
5VDC input.

Address bus outputs. Unidirectional bus
used to address memory and I/O devices.
The address bus can be disabled by con-
trolling the AEC input.
Dc ground connection.
I/O bidirectional port. This port can be
controlled via memory locations 0000 and
0001.

0001 = Output register
0000 = Data direction register
Bidirectional data bus. This is the bus that
passes the data to or from any I/O device
or memory.

Read/Write output. The processor gener-
ates a low level when writing, and a high
level when reading. This signal is usually
decoded for read or write operations to
memory or I/O.

Phase 2 output. The processor generates
this clock signal from the phase 1 clock
applied. The two clock signals are 180
degrees out of phase. The phase 2 clock
is used in decoding I/O and memory on
the positive half cycle.
40 RES Reset input interrupt. A low pulse causes

a jump to a subroutine specified by FFFC
and FFFD, which will initialize all proces-
sor controlled devices. This occurs during
a power up sequence.

6 VCC

7-20 A0-A15
22,23

21 GND

24-29 P0-P5

30-37 DB0-DB7

38 R/W

39 02

SCHEMATIC #251138 SHEET 2 OF 2

— -iVc

sound carrer select c/w^ only )

SHORT S.SMHe FOR G./ML
OPEN 6 MHx FOR I. PAL-
ALL CAPAC/TOR VALUES ARE
IN mF.

ALL RESISTORS ARE 1/4 WATT
tSYo.

CLOCK CIRCUIT I

ITEM

NTSC

PAL

Y1

H.StdfB

1 7.734472

C70

NZ200

/SPF±S%
N3300

R24>

oa

/ooa

R32

300 a

3 jo a

R33

3?OXl

/ooa

C/07

rOuF

POWER INPUT CN7
( 7P/A/ M4L6 DIN )

VC SHOULD BE USED 70 DRIVE
ONLY DEVICES INDECATED .

MOTES-UNLESS OTHERWISE SPECIFIED :

27

r^

n

SF-1 U

O "

4

CB3-

•0

••• r _

M* , , ,

::ii

*8S8taX8

« i

«s»

1

M

j""™' '\

Ml

r .

'

l u !

M

r .

'

191

rili 1

•M

„" W '

V\> 1

r\

**

"55

O

S8&

CM

o
If)

CM

=tfc

H

O
>
<

<
O

28

PARTS LIST - PCB ASSEMBLY #250425-01
C — Indicates Commodore Stocked Part Number

INTEGRATED CIRCUITS

U1,U2

U3

U4

U5

U6

U7

U8

U9-U12

U13

U14

U15

U16

U17

U18

U19

U20

U21-U24

U25

U26

U27

U28

U31

6526 CIA

2364 Basic ROM

2364 Kernal ROM

2332 Char ROM

2114L-20 RAM

6510 /* Processor

7406

7416

4164 (200 nS)

74LS257

74LS258

74LS139

4066

82S100 PLA

6581 SID

6567 VIC II

LM556

4164 (200 nS)

74LS257

74LS373

74LS08

4066

7701/8701

C 906108-01

C 901226-01

C 901227-03

C 901225-01

901453-01

C 906107-01

901522-06 sub:

901522-14

901505-01

901521-57

901521-58

901521-18

901 502-01

C 906114-01

C 906112-01

C 906109-01

901 523-03

901505-01

901521-57

901521-29

901521-03

901 502-01

C 251527-01

TRANSISTORS

Q1
Q2-4

TIP29 A
2SC1815

902653-01
C 902693-01

DIODES

CR1
CR2
CR4

CR5,6
CR9,
CR12-16,
100-105

2.7V Zener IN4371 906103-02

6.8V Zener IN754A

Bridge S2VB10 C 251026-01 sub:
DBA20B C 251026-02 sub:
DBA20C C 251026-03

Rectifier IN4001 900750-01

IN4148 sub:

IN914

RESISTORS - All values are in ohms- 1/4 W,
5%, unless noted otherwise.

R1
R2
R3
R4
R5
R6
R7

3.3K

470

100K

1K

560

1K

10K

R26
R31
R33
R34
R35
R37
R38

3.3K

180

47K

47K

470K

2.7K

1K

RESISTORS (Continued)

R39
R41
R42
R43
R44
R45

390

1M

82

3.3K

3.3K

3.3K

R50

R51

R60

R100

R101

1M

1.5K

100

1K

22K

RESISTOR PACKS

RP1,2

RP3

RP4
RP5

330, 8 Pin (Bourns No.
4308R-1 02-330)
3.3KQ, 8 Pin (Bourns No.
4308R-101-332)
3.3K0, 10 Pin, 1/4 W
1K0, 6 Pin

CAPACITORS

C1-7

C9

C10.11

C12

C13

C15

C19

C20

C22

C23

C24

C31 ,33,34

C37

C38

C39-46

C48

C50,51,53

C59

C88

C90

C91

C93

C101

C102

C1 50-1 52

C153

C154

C200

C204

C205

CT1

Ceramic

Ceramic

Ceramic

Ceramic

Electrolytic

Tantalum

Electrolytic

Film

Ceramic

Ceramic

Electrolytic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Electrolytic

Electrolytic

Electrolytic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Ceramic

Trimmer

.1 jtF,

.1 /*F,

470 pF,

.1 /iF,

10 iiF,

4.7 ^F,

2200 fiF,

.22 M F,

.1 nF,

360 pF,

390 pF

22 ^F,

.1 pF,

1000 pF,

51 pF,

.1 /*F,

1800 pF,

.1 /*F,

.1 /*F,

1000/tF,

470 iiJF,

100/tF,

1800 pF,

.1 ftF,

.1 IiF,

470 pF,

68 pF,

470 pF,

• 1 IiF,

150pF,

220 pF,

40 pF

25V

25V

50V, 10%

25V

25V, +50%, -10%

16V, 20%

16V

100V, 20%

25V

50V, 10% sub:

25V, +50%, -10%

25V

50V, 10% B

50V, 5% SL

25V

50V, 10% B

25V

25V

25V

50V

16V, +50%, -10%

50V, 10% B

50V, +80%, -20%

25V

50V, 10%

50V, 5%

50V, 10%

25V

50V, 10%

50V, 5%

29

PARTS LIST - PCB ASSEMBLY #250425-01 (Continued)
C — Indicates Commodore Stocked Part Number

r^

CONNECTORS

MISCELLANEOUS (Continued)

CN1

CN4

CN5

CN6

CN7

CN8,9

CN10

Header Assy, 20 Pin 903331-20

6 Pin Din C 903361-01
8 Pin Din C 325573-01
44 Pin Card Edge C 906100-02

7 Pin Din C 251116-01
Plug Assy, 9 Pin MINID C 251057-01
Header Assy, 3 Pin 903332-03

SW1
VR1
VR2

M1
F1

Rocker Switch DPDT 904500-01

Voltage Regulator

MC7812CT 901527-01

Voltage Regulator

MC7805CT 901 527-02

Modulator C 251696-01

Connector Panel

(Power, ON, OFF) 251095-01
Cartridge Guide 326116-01

Fuse, Normal Bio, 250V, 1.5A

MISCELLANEOUS

L1
L4
L5

Y1

Coil Inductor 2.2 /tH 901 1 51 -1 7
Line Filter Assy C 251701-01
Coil Inductor 1 .2 /tH 901 1 52-01

Crystal 14.31818 MHz C 251467-01

n

r\

30

MODULATOR SCHEMATIC #251696

COLOR IN o

o COLOR OUT

LUMUN O

RF OUT

GROUND

AUDIO /N o

NOTES

1. D1,DZ .MAtStK OR EQUIVALENT

2. D3 : MAS 7 OR EQUIVALENT

3. D4, DS : /SS/<?8 OR EQUIVALENT

4. D& \HZ-7A1 OR EQUI VA LEN T

5. Qf,Q2 : 2SC2403 OR EQUIVALENT

6. Q3,Q4:2SC2778 OR EQUIVALENT

7. QS I 2SC2/Z0Y OR EQUIVALENT

8. COMPONENT PARTS VALUE :/?-&, C *F, L=H

SCHEMATIC #251469 SHEET 1 OF 2

/7.7J447 MHl-PAL CHSff

NOTES:

DOT CLOCK

S./SM/k

tCOLOX

/ 4. 3/8/3 M//z

* /

/. 02 MHz

r /

/4.3/S/8M//*

U3t

770/

U/9

6S67

U/7

7 700

NTSC-/NACTI\/£

CARTRlt&E/SxPANSION (+1P/N FEMALE ) CN6

31

PIN
ASSIGNMENT

1-7/39 DB0-DB7
8 IRQ

DB6-

1

40

-VCC

DB5-

2

39

-DB7

DB4-

3

38

-DB8

10

CS

DB3-

4

37

-DB9

11

19

R/W
RA

DB2-

5

36

-DB10

DB1-

6

35

-DB11

1 Z.

DM

DBO-

7

34

-A10

IRQ-

8

33

-A9

LP-

9

32

-A8

CS-

10

31

-A7

13

VDD

R/W-

11

30

-A6("1")

14

COLOR

BA-

12

29

-A5(A13)

VDD-

13

28

-A4(A12)

15

SYNC/

COLOR-

14

27

-A3<A11)

16

LUM
AEC

SYNC/LUM-

15

26

-A2(A10)

AEC-

16

25

-AKA9)

PHO-

17

24

-A0(A8)

RAS-

18

23

-A11

CAS-

19

22

-PHIN

VSS-

20

21

-PHCL

U19 - 906109-01

MULTIPLEXED

ADDRESSES IN PARENTHESES

17 PHO

18 RAS

19 CAS

20 VSS

21 PHCL

22 PHIN

23-24 A0-A13

35-38 D8-D11
A8-A11
40 VCC

Processor data bus connections. Bidirec-
tional data.

Interrupt output. Generates a interrupt
signal to the processor indicating service
is needed. The light pen input can be
acknowledged thru use of this interrupt.
Chip select input. A low signal selects the
VIC 11.

Processor read/write connection.
Bus available output. A low pulse output
indicates the VIC 1 1 chip wants controls
of the processor network to process
faster video operations that the system
clock can handle.
12VDC input.

Output contains chrominance, color
reference burst, and color of display data.
Output containing video, horizontal and
vertical sync, and luminance information.
Address enable output. This is usually
connected to the processor AEC input,
controlling the address bus.
AEC = processor address bus disabled,

refresh ram.
AEC = 1 processor address bus enabled.

This allows transparent refresh

operations.
Phase output. Generated from the
phase in signal.

Row address strobe output. Selects proper
row when addressing dynamic ram for
read/write operations or refresh.
Column address strobe output. Selects
proper column when addressing dynamic
memory for read or write operation.
Ground connection.
Color clock, 14.31818 MHZ NTSC.
Clock input. Determines the dot transfer
rate to the display.

Dual function address bus. During a micro-
processor read or write operation (AEC =
1), AO thru A5 are inputs used to address
47 internal registers. When AEC = =
02 is low, then AO thru A13 are outputs
used to refresh dynamic memory.
Data bus extension. Color display memory
data.

Address bus extension. Color display
memory addressing.
5VDC input.

SCHEMATIC #251469 SHEET 2 OF 2

QllSD880/rp2?B

{'NTRST >

4 Sound carreR sblbct (?#l omly)

SHORT ^SMHs FoX &m.

opBKt 6 MHz

J. PAL

CAPACITOR VALUES Am IN MF

ARE '/4 WATT tSVo.

POM BR INPUT CN7

( 7 PIN MALE D/AJ )

VC ^THOVlb 3£ AtS£& TO £>R/VE
O/^LY £EV/C£S /A/0ECATED .

NO TES - t/A/£ £SS OTH£X)Y/SE SP£C/F/££> :

32

Cm. commodore

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Service Documentation

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PLACE

STAMP

HERE

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